1. Field of the Invention
The present invention relates to an ink, an ink cartridge, an ink-jet recording method, and an ink set.
2. Description of the Related Art
In recent years, ink-jet recording technologies have been used in a wide range of fields, and an ink usable in various uses has been desired. Pigment inks, in which pigments are used as coloring materials, have been utilized especially in applications where the fastness property is taken very seriously. However, the pigments have a specific issue that scattering of light occurs easily because the pigments are present as particles. In particular, in the case where a recording medium is glossy paper, there is an issue that a so-called bronze phenomenon occurs, in which an image recorded on the glossy paper glares in such a manner as metallic luster, or reflected light takes on a color different from the color intrinsic to the pigment depending on the observation angle of the recorded material.
In order to solve the above-described issues, various proposals have been made previously. For example, it is disclosed that the bronze phenomenon is suppressed by using a phthalocyanine pigment and a polymer emulsion in combination (refer to Japanese Patent Laid-Open No. 2000-351931). The bronze phenomenon is also recognized remarkably in the case where a monochrome image is recorded by using an achromatic ink and, therefore, suppression thereof has been desired strongly. Regarding this problem, for example, an attempt to include carbon black and another coloring material to reduce the bronze phenomenon and reduce the property of taking on yellow and the property of taking on red has been proposed (refer to Japanese Patent Laid-Open No. 2006-206701). In order to suppress the property of taking on yellow of carbon black, there is a proposal related to an ink containing carbon black and another coloring material (refer to Japanese Patent Laid-Open No. 2006-063101). Furthermore, there is a proposal related to an apparatus in which the bronze phenomenon of an image formed by superposing a plurality of inks can be suppressed through image processing to perform color separation in such a way as to minimize a bronze value (refer to Japanese Patent Laid-Open No. 2008-143135).